The invention relates to a container formed of hingedly connected plates such that the container is collapsible.
Amongst other documents, containers of this type are known from WO 94/11259 A, WO 95/13970 A and WO 97/41037 A, filed by the predecessor of the present applicant. Containers of this type consist of several flaps, one of which forms the base whilst the others form side walls, and the flaps can be folded into a position in which they are parallel with one another for the purposes of cleaning or for transporting empty, in which case they are folded into a position parallel with the base, either extending out beyond it or inwards so that they lie on the base.
In order to transport goods, the flaps forming the side walls are swung upwards into a position perpendicular to the base and secured to one another.
The devices allowing the individual flaps to be pivoted are provided in the form of hinge pins, which are retained at a distance from the front edges of the individual flaps by means of connecting links and which locate in grooves of the other flap. In some of these containers, the flaps can be separated from one another by displacing the individual flaps relative to one another in a direction of the longitudinal axis of the hinge pins.
A container is also known from WO 96/11144 A1 and from DE 42 01 145 A1 and is of a design similar to those described above. With these containers, the first of the above-mentioned publications proposes a design in which one of the guide sleeves for the hinge pin has slits and is elastically deformable in a radial direction allowing a pivoting action to reach and lock into the position relative to the flap forming the base, whilst the rest of the hinge mechanism is designed so that when the flaps forming the side walls are in the upright position the hinge pin is relieved of vertical stress, i.e. stress applied in a direction perpendicular to the flap forming the base is deflected.
However, all the containers described above have proved incapable of meeting all the requirements placed on them in terms of strength and the securing elements have not proven sufficiently capable of taking the strain.
Accordingly, the objective of the present invention is to provide a container which is capable of exhibiting a high degree of resistance to the increased strain placed on them when transporting goods, as well as the stress applied to the containers from outside, and which is capable of taking the weight of the containers above when stacked one on top of the other.
The above needs are addressed and other advantages are achieved by a container in accordance with the present invention. In one preferred embodiment of the invention, the container comprises a base and a plurality of flaps, each of the flaps being hingedly connected at a front edge thereof to the base by at least one hinge mechanism. Each hinge mechanism comprises at least one hinge pin affixed to the corresponding flap and a groove formed in the base for receiving the hinge pin, the hinge pin extending parallel to the front edge of the flap and being affixed to the front edge by a connecting link that extends therebetween such that the hinge pin is spaced at a distance from the front edge. The groove is formed in a peripheral ridge that projects above a surface of the base, the groove extending along a longitudinal axis thereof and having an opening extending laterally thereinto through which the hinge pin can be inserted into the groove. The groove has an end region forming a housing chamber for an end region of the hinge pin, the end region of the hinge pin having a length projecting beyond the connecting link in the direction of the longitudinal axis of the groove. The housing chamber is defined by a retaining shoulder preventing the hinge pin from being laterally withdrawn from the groove. The peripheral ridge defines a recess therein so as to provide a region for the connecting link of the hinge pin to pivot about the longitudinal axis of the groove, the recess for the connecting link being delimited in the direction of the longitudinal axis by the retaining shoulder and a stop. A distance between the retaining shoulder and the stop is at least as great as a length of the connecting link in a direction parallel to the hinge pin but not greater than a sum of the length of the connecting link and the length of the end region of the hinge pin. Accordingly, the container is advantageous due to fact that the layout of peripheral ridges increases the strength of the flap forming the base and due to the fact that the linking devices are mounted above the surface of the base so that the flaps forming the side walls can be positioned and released from the base in a horizontally restricted position on the base, whilst, in the erected state, the hinge pins can be arranged so that they are protected and covered towards the exterior. Consequently, these delicate and sensitive hinge pins of the hinge arrangements are better protected, for example against the prongs of fork lifts or from being too tightly packed together or from impact against the side wall of a vehicle.
A further embodiment of the invention has an advantage in that the hinge pin is pretensed by a minimum degree relative to the bearing regions in which it is mounted in the groove in order to provide additional space so that, even when subjected to stress caused by impact and vibrations, the hinge pin is still adequately guided and retained in the groove. At the same time, however, any undesirable excessive strain on the hinge pins which might cause them to break or bend can be safely avoided. This enables a higher vertical load to be applied, even when the containers are stacked one on top of the other, and ensures that the hinge pins will be more efficiently retained in the grooves in the event of impact from the outside acting on the flaps forming the side walls and affecting the interior of the container.
Another embodiment provides a surprisingly advantageous design whereby the flaps, which can be adjusted relative to one another, are folded together in the upright position and located, the arrangement of connecting seats having elastically deformable retaining elements designed to provide guidance and support in different spatial directions, thereby advantageously preventing any bowing in the corner region where the flaps are joined to one another. The solution outlined in claim 4, which offers a solution in its own right, allows the upright flaps bearing one against the other to be interlocked in flaps arranged approximately perpendicular to the flaps forming the base in different spatial directions so that even in the event of high vertical or horizontal loads, the flaps abutting with one another will be prevented from weakening in different spatial directions and no damage or similar is caused to the container even when subjected to extreme stress by the goods contained therein or by externally acting forces applied by conveyor means.
Other advantageous embodiments are described in the following detailed description.